I got my Donaldson air cleaner in the mail today. I bought it off from ebay hoping it would fit my Cub. The description said that it came off an A, and I have been told that the ones from an A will fit a Cub. I opened it up, and it is HUGE. The opening for the air cleaner stack is 2 1/4 inches. Does anyone know what it will fit? Maybe Grandpa's H?